Radio tube or the like



M. R. SCHULTE RADIO TUBE OR THE LIKE June 17, 1941,

Filed July 20, 1959 INVENTOR M2704 A? 50/00! a w/w TTORNEY Patented June17, 1941 RADIO TUBE OR THE LIKE Milton R. Schulte, West Orange, N. J.,assignor to Tung-Sol Lamp Works Inc., Newark, N. J., a

corporation of Delaware Application July 20, 1939, Serial No. 285,470

3 Claims.

This invention relates to radio tubes and the like electric devices.

One object of the invention is a novel and improved radio tube.

A further object of the invention is a novel and improved radio tubewhich will be economical to manufacture and efficient in operation.

A feature of the invention is the elimination of the usual glass stem ofthe tube and the substitution therefor of a plain disk or button ofglass with consequent saving in [cost and economy in available spacewithin the tube.

A further feature of the invention is the Ibringing of the lead wiresthrough the seal between the disk and bulb at widely separated points tosimplify the construction and to reduce the capacity effect between theleads, particularly that between the control grid lead and anode lead.

Other features of the invention will become apparent as the descriptionproceeds.

For an understanding of the invention, reference may be had to theaccompanying drawing, of which-- Fig. 1 is a perspective viewillustrating one stage in the assembly of the mount and the glassenvelope of a tube embodying the invention;

Fig. 2 is a sectional view along the line 2-2 of Fig. 1 but showing theglass envelope sealed to the base;

Fig. 3 is a perspective View of the mount of a tube illustrating anotherembodiment of the invention; and

Fig. 4. is a vertical sectional View along the line 44 of Fig. 3 butshowing a completed tube.

In the embodiment of the invention illustrated in Figs. 1 and 2, a plaindisk 2 of glass or the like forms the lower closure of the tube, thedisk 2 being sealed to the tubular envelope 4 of glass or the like asshown in Fig. 2. All of the lead wires 6, l, 8, 9 and It! for theelectrode assembly l2 are brought out through the seal between the diskand envelope at widely separated points; the leads 6 and 9 for thecontrol grid and anode respectively being brought out at diametricallyopposite points of the disk 2. The electrode assembly 12 may besupported in any suitable manner within the tube. In the particular tubeillustrated, the electrode assembly 12 is of the type having vanes Mwhich frictionally engage the inner walls of the envelope 4 and hencelittle, if any, additional support is required. Such additional supportmay be provided, as shown, by the grid lead 6 and anode lead 9.

In manufacturing the new tube, the lead-in conductors are first bentaround the edge of the disk 2. The elements of the electrode assemblyare then connected directly to the lead-in conductors; the conductors Iand Ill preferably being first passed through an insulating block iii ofmica or the like. The cylindrical glass enve lope 4, which has firstbeen tubulated at its upper end and provided with an exhaust tube 13, isthen slid over the assembly and its open lower end fused about the disk2 and lead-in conductors. The tube is then heated, and evacuated or gasfilled, as desired, in the usual manner and the exhaust tube sealed oil.

The tube illustrated in Figs. 3 and 4 differs from that of Figs. 1 and 2in that additional supporting means are provided for the electrodeassembly. In this latter embodiment of the invention a disk 2 formingthe base of the tube is provided with upstanding insulating members 20,which may be of glass and fused directly to the disk 2'. The members 29are vertically slotted at their upper ends to receive the vanes 14 asshown. This makes a compact unitary arrangement of base and electrodeassembly ready for sealing into the envelope 4. As with the tube ofFigs. 1 and 2, the lead-in conductors are brought out at separatedpoints through the seal between the disk 2' and envelope 4, with theleads 6 and 9 separated the maximum distance.

From the above description it will be apparent that the inventionprovides a tube in which the cost of manufacture is materially reducedas compared to that of the type of tube having the usual relativelyexpensive glass stem both because of the lesser cost of the simple diskof glass or the like forming the base of the tube, and because therewill be less breakage during the sealing operation. Furthermore, thebringing out of the lead-in conductors through the seal at widelyseparated points reduces the capacity effects between the leads,particularly between the grid and anode leads, and hence improves theoperation of the tube. The provision of the disk base also increases theusable space within the envelope, permitting either a larger electrodeassembly or a smaller envelope as compared with tubes now on the market.

Although the invention has been described as embodied in an improvedradio tube, obviously certain features thereof are applicable to othertypes of glass enclosed electrical devices, such as incandescent lamps,flash-lamps or the like.

The following is claimed:

1. A radio tube comprising in combination, a

disk of refractory material, an envelope of refractory material sealedto the periphery of said disk to form an enclosure therewith, anelectrode assembly within the enclosure, lead-in conductors for theelectrode assembly, said conductors passing through the seal betweensaid disk and said envelope at separated points and upwardly projectinginsulating members secured-to-said disk for supporting said assembly.

end of the envelope and lead-in conductors for the electrode assembly,the improvement comprising forming the closure of a disk sealed at itsperiphery to the envelope with the lead-in conductors passing throughthe seal and with the lead-in conductors for the anode and control griddiametrically disposed in the seal.

3. Aradio tube according to claim 2 including upwardly projectinginsulating members secured 2. In a radio tube comprising an envelope, an10 to said disk for supporting said assembly.

electrode assembly including an anode and a control grid within theenvelope, a closure for one MILTON R. SCHULTE.

